Debris cleanup tools that deliver pressurized fluid down a tubing string into an eductor device are illustrated in U.S. Pat. Nos. 6,276,452 and 7,789,154. The eductor exhaust is into the surrounding annulus where the flow splits. Some of the flow goes downhole to a mill that creates the cuttings and that flow enters the mill and takes the cuttings into a debris collection housing. The large cuttings are stopped by a screen and settle out in a debris retention space. The remaining flow with some small debris that passes the screen is sucked into the eductor inlet. The eductor outlet flow that does not travel down the annular space around the tool goes up to the surface in that same annular space. The eductor is installed as a bushing that is fixed in the housing of the debris collection device.
Once such devices were installed in a string and run into the well, they provided the above described flow pattern but had no facility to alter the flow pattern for another purpose. It was determined to be desirable to convert the flow scheme of the tool as described above to be able to flow through the tubing as before as well as to be able to shut off the eductor outlet and direct pressure through the debris collector body and out a lower end through the mill. Being able to do this is advantageous for the reason that the tool can be flowed internally in a reverse direction to the normal up flow from the mill and up to the eductor. In the event the tool gets obstructed this is a good way to get it cleared. An option to revert back to the original flow scheme can also be incorporated so that debris removal can take place after a blockage is removed. In a preferred embodiment the eductor is axially shifted to change the flow scheme through it. This can be configured as a onetime movement or cycling back and forth between the end positions is possible. Those skilled in the art will better appreciate more aspects of the invention from a review of the description of the preferred embodiment and the associated drawings while recognizing that the full scope of the invention is to be determined by the appended claims.
Older debris collection devices such as U.S. Pat. No. 4,276,931 used a complex valve arrangement where flow through the valve actuated it to move axially and such axial movement compressed a rubber ring to seal off a central passage and at the same time open a lateral port into an internal annulus that led to an eductor. Separate flow passages were used for normal reverse flow into the mill to collet debris on pivoting fingers as opposed to flow straight through the valve member for circulation flow through the mill such as when running in to agitate the debris already in the wellbore and to facilitate rapid running in.